Dissertation/Thesis Abstract

Searching for new phenomena in high energy cosmic rays
by Cholis, Ilias, Ph.D., New York University, 2010, 355; 3428037
Abstract (Summary)

The focus of my work has been attempting to study how cosmic rays may help us understand the nature of dark matter. This question is at the intersection of particle physics and astrophysics, and involves questions of particle physics model building, production and propagation of cosmic rays, and connections to collider physics. My interest has been the properties of various DM candidates that would annihilate into Standard Model particles producing eventually high energy e+ and e - as well as p and that could influence their locally measured ratios at high energies.

I have focused on models that produce significant amounts of hard positrons, and have considered the propagation of the resulting cosmic rays in the galaxy, namely electrons positrons and antiprotons as well as some heavier nuclei. Among the experiments whose data I have studied are HEAT, PAMELA, ATIC and Fermi.

An other interesting aspect has been the possible explanation of the "microwave WMAP Haze" that Finkbeiner has calculated from CMB data at the central part of the galaxy, and its inverse Compton scattering counterpart the Fermi γ-ray haze. The connection to synchrotron radiation and inverse Compton scattering from high energy e- and e+ of annihilating DM origin has also been part of my work. Moreover the connection of those results to the results from PAMELA and ATIC/Fermi within the same DM framework has been one of the goals of my studies.

As an alternative to DM, Pulsars could be used to explain the recent results from the PAMELA Collaboration. As Pulsars spin down their energy high numbers of electron and positron pairs are produced via pair creation from X-rays emitted by high energy electrons at the poles of the Pulsars. The implications of the resulting injected into the ISM e± to the local spectra has also been part of my work. Also the significance of millisecond pulsars in the bulge and their implications to both the microwave and the γ-ray Haze, in combination with existing DM models has been part of my research work.

Indexing (document details)
Advisor: Weiner, New
Commitee: Gabadadze, Gregory, Grier, David, MacFadyen, Andrew, Scoccimarro, Roman
School: New York University
Department: Physics
School Location: United States -- New York
Source: DAI-B 72/01, Dissertation Abstracts International
Subjects: Astrophysics, Particle physics
Keywords: Cosmic rays, Dark matter, Pulsars
Publication Number: 3428037
ISBN: 978-1-124-33277-2
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